What is the nature of the pain? If it is dull aching sort of a feeling of heaviness then there is likelihood of it being a varicocele
provided there is swelling at the upper end. If is severe and referred to the lower abdomen it can be a mild attack of torsion. If it is intermitent but localized then it may be related to the cyst
. Get a scrotal USg as well as scrotal doppler as well as a urine examination.